Not sure about the make but think it is Wilwood.
I should probably have started all this by saying this is a UK Cobra with...wait for it..a 383 SBC in it (they are all the rage in the UK, honest!
). Running a Tremec TKO II.
So reducing the master cylinder diamter (say from .875 to .75) will reduce the slave cylinder throw. Hmmm...I think that would make things even worse.
Paul